Homogeneous stabilizer compositions for vinyl halide polymers

ABSTRACT

In accordance with the present invention, it has been found that liquid stabilizer compositions for vinyl halide polymers that are compatible with and form stable mixtures with epoxidized glycerides can be prepared by a process which comprises heating a non-homogeneous mixture comprising (A) at least one epoxidized glyceride, (B) at least one hydrocarbon-soluble, (B-1) basic alkali or alkaline earth metal salt of an alkyl phenol, or (B-2) basic alkali or alkaline earth metal salt of a monocarboxylic acid, and (C) a hydrocarbon diluent, at an elevated temperature until the mixture is homogeneous. Generally, the metal salts are alkaline earth metal salts such as calcium and barium, and the basic alkaline earth metal salt utilized in this system is a salt of an aliphatic monocarboxylic acid prepared in the presence of a phenol promoter. The invention also relates to stabilizer compositions thus prepared and to stabilizer compositions optionally containing (D) substantially neutral polyvalent metal salts of carboxylic acids and/or (E) organic phosphites. Vinyl halide polymer compositions comprising a vinyl halide polymer and a stabilizing amount of the homogeneous stabilizer compositions of the invention also are described and claimed.

BACKGROUND OF THE INVENTION

This invention relates to a novel method for the preparation ofhomogeneous stabilizer compositions for vinyl halide polymers, thestabilizer compositions so prepared, and to vinyl halide polymersstabilized therewith. More particularly, the invention relates to aprocess for preparing homogeneous compositions comprising epoxidizedglycerides such as vegetable oils, and hydrocarbon-soluble basic alkaliand alkaline earth metal salts of alkyl phenols and/or monocarboxylicacids.

Many organic polymers, more particularly halogen containing organicpolymers are conveniently and economically processed into usefularticles of commerce by methods employing heat to melt or soften thepolymer. The use of such heat can be and often is detrimental to thepolymer, especially where the polymer is exposed to high (100° C. to200° C.) processing temperatures for any extended period of time. It iswell known that many organic polymers, including halogen containingorganic polymers, will undergo color changes and various other physicalchanges upon exposure to high temperatures over a period of time unlessproperly protected. The color change is gradual but visually perceptableduring short-term exposure to high processing temperatures, but onexposure to high processing temperatures the change in color acceleratesand becomes greater in intensity. Color changes occuring during thefirst several minutes of exposure to high processing temperatures arecommonly referred to as early color or early discoloration. Avoidance ofsuch early color or early discoloration is particularly important wherewhite or light colored products are to be produced. It is of course alsoimportant to prevent or reduce discoloration and deterioration of theorganic polymer during extended exposure to high processing temperaturesas may be encountered in some processes or fabricating methods.

A variety of stabilizer systems have been suggested and used to inhibitor prevent this deterioration. These stabilizer systems are for the mostpart presumed to act in such a manner as to neutralize hydrogen halidethat is generated to prevent further dehydrohalogenation which couldresult because of the presence of free hydrogen halide. Among thestabilizer systems that have been suggested and used in the prior artare oil-soluble salts of such metals as barium, cadmium, zinc,zirconium, tin, calcium. Generally, the above metal salt stabilizers areused in combination with one or more organic phosphites.

In many applications, the stabilizer systems incorporated into vinylhalide polymers will contain an auxiliary stabilizer which is anepoxidized vegetable oil, an epoxidized fatty acid, or an ester of anepoxidized fatty acid such as epoxidized soybean oil, epoxidized talloil, and butyl epoxy stearate.

In the commercial use of stabilizer systems for vinyl halide polymers,has become common practice to prepare mixtures of the variousstabilizers which facilitate the handling and storage of thestabilizers. For example, useful stabilizer systems comprising blends ofoil-soluble salts of polyvalent metals, organic phosphites, andauxiliary stabilizers such as epoxidized soybean oils are often preparedfor use as needed.

A variety of oil-soluble salts of monovalent and polyvalent metals havebeen utilized as stabilizers for vinyl halide polymers. The metalsinclude the alkali metals, zinc, calcium, tin, barium, aluminum,strontium, zirconium and magnesium. The metal salts may be neutral saltsalthough basic or "overbased" metal salts are preferred since thesecontain larger amounts of the metal. In some applications, mixtures ofneutral and metal basic salts are utilized such as mixtures of neutralcadmium carboxylates with overbased barium phenates, carboxylates and/orsulfonates.

U.S. Pat. No. 4,159,973 describes stabilizer systems for vinyl halideresin compositions which comprise mixtures of (a) specified overbasedbarium salt complexes that are compatible with epoxidized vegetable oil,(b) a polyvalent metal salt component, (c) at least one organicphosphite, and (d) an aromatic or aliphatic hydrocarbon solvent.Examples of the polyvalent metal salts include cadmium, zinc, zirconium,tin and calcium salts of aromatic as well as aliphatic carboxylic acids.The organic phosphites may be secondary or tertiary aryl, alkyl oralkaryl phosphites. It is reported that vinyl halide resin compositionscontaining such stabilizer systems are characterized by excellent heatand light stability, color and clarity.

An anti-yellowing additive for stabilizing vinyl chloride polymers isdescribed in U.S. Pat. No. 4,252,698. The additive comprises the mixtureof at least one overbased sulfonate or phenolate compound of lithium,sodium, potassium, magnesium, calcium, strontium, barium, zinc,titanium, aluminum, zirconium or tin, and a 1,3-di-ketone compoundhaving about 5 to about 30 carbon atoms or a metal salt thereof whereinthe metal may be any one of the metals described above for the overbasedsulfonate or phenolate compound.

U.S. Pat. No. 3,194,823 describes barium- and cadmium-containing organiccomplexes useful in stabilizing halogen-bearing polymeric compositions.In general, the complexes are prepared from a mixture comprising (a) analcohol, (b) an aliphatic monocarboxylic acid compound, and (c) amixture of barium and cadmium bases optionally in the presence of aphenol. Such cadmium- and barium-containing basic complexes can beutilized in vinyl halide polymers in combination with other stabilizingagents such as epoxidized soybean oil and organic phosphites.

The polyvalent metal components of the stabilizers which have beenutilized for vinyl halide polymers usually contain a barium compoundwhich may be a salt of a monocarboxylic acid such as octanoic acid,neodecanoic acid, or naphthenic acid; a salt of an alkyl phenol such asoctyl phenol, nonyl phenol, etc.; or an overbased barium salt complex.The use of overbased barium salt complexes has increased in recent yearsbecause the overbased salts contain high amounts of barium such as, forexample, 21 to 35% barium or higher.

Overbased barium salt complexes are well known, and various proceduresfor preparing such overbased barium salt complexes from carboxylicacids, sulfonic acids and alkyl phenols using an acidic gas such ascarbon dioxide or sulfur dioxide to reduce the basicity are disclosedin, for example, the following U.S. Pat. Nos.: 2,616,904; 2,760,970;2,767,164; 2,798,852; 2,802,816; 3,027,325; 3,031,284; 3,342,733;3,533,975; 3,773,664; and 3,779,922.

While many overbased barium salts such as the overbased barium alkylphenate complexes described in some of the above patents are effectivestabilizers for vinyl halide polymers, they often are incompatible withepoxidized soybean oil and other epoxidized vegetable oils. When theoverbased barium compounds are combined, for example, with conventionaloil-soluble cadmium and/or zinc carboxylic acid salts and organicphosphites, and the resulting stabilizer system is blended with anepoxidized vegetable oil, the resulting blend generally becomes cloudyas the incompatible components precipitate. Because such blends are nothomogeneous, they present handling and storage problems.

U.S. Pat. No. 4,159,973 describes overbased barium salt complexes thatare compatible with epoxidized vegetable oils. The barium salts areobtained by forming a reaction mixture that consists essentially of abasic barium compound, an alkyl phenol and an inert organic diluentwherein the mixture contains at least 0.75 mole of alkyl phenol per moleof the barium compound, and the reaction mixture is maintained at atemperature of at least 180° C. while treating it with an acidic gassuch as carbon dioxide until the product is substantially neutral. Ifless than 0.75 mole of alkyl phenol is included in the mixture, and themixture is treated with carbon dioxide at a temperature below 180° C.,the barium compound obtained is reported to be incompatible withepoxidized vegetable oils.

U.S. Pat. No. 4,401,779 issued Aug. 30, 1983 to Bae et al describeshomogeneous liquid stabilizer systems which impart heat and lightstability to polyvinyl chloride resins. The systems contain as theessential and only stabilizers, a liquid barium carbonate-barium alkylphenate and a cadmium salt of a branch chain aliphatic carboxylic acidhaving from about 8 to about 10 carbon atoms, or mixtures thereof in anamount of at least which 85% with up to about 15% of one or more cadmiumsalts of aromatic carboxylic acids having from about 7 to about 11carbon atoms and saturated and unsaturated straight chain aliphaticcarboxylic acids having from about 12 to about 22 carbon atoms. Thebarium and cadmium salts are present in amounts sufficient to form ahomogeneous liquid.

SUMMARY OF THE INVENTION

In accordance with the present invention, it has been found that liquidstabilizer compositions for vinyl halide polymers that are compatiblewith and form stable mixtures with epoxidized glycerides can be preparedby a process which comprises heating a non-homogeneous mixturecomprising (A) at least one epoxidized glyceride, (B) at least onehydrocarbon-soluble, (B-1) basic alkali or alkaline earth metal salt ofan alkyl phenol, or (B-2) basic alkali or alkaline earth metal salt of amonocarboxylic acid, and (C) a hydrocarbon diluent, at an elevatedtemperature until the mixture is homogeneous. Generally, the metal saltsare alkaline earth metal salts such as calcium and barium, and the basicalkaline earth metal salt utilized in this system is a salt of analiphatic monocarboxylic acid prepared in the presence of a phenolpromoter. The invention also relates to stabilizer compositions thusprepared and to stabilizer compositions optionally containing (D)substantially neutral polyvalent metal salts of carboxylic acids and/or(E) organic phosphites. Vinyl halide polymer compositions comprising avinyl halide polymer and a stabilizing amount of the homogeneousstabilizer compositions of the invention also are described and claimed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The liquid homogeneous stabilizer compositions of the present inventionare prepared by heating a non-homogeneous mixture which comprises (A) atleast one epoxidized glyceride, (B) at least one hydrocarbon-solublebasic alkali or alkaline earth metal salt, and (C) a hydrocarbon diluentat an elevated temperature until the mixture is homogeneous.Non-homogeneous mixtures of such compositions can be renderedhomogeneous generally by heating the mixture at temperatures within therange of from above ambient temperature to about 150° C. or higher forperiods of from a few minutes to about one or two hours or more. Thehomogeneous mixture remains homogeneous when cooled to ambienttemperature, and remains homogeneous over an extended period of time.

It also has been observed that once the above mixtures are renderedhomogeneous, other standard stabilizers for vinyl halide resins can beblended into the homogeneous mixture without destroying the homogenityof the mixture. Examples of standard stabilizer compositions which canbe blended into such mixtures and which will be described in more detailhereinafter include (D) substantially neutral metal salts of carboxylicacids and (E) organic phosphites.

The epoxidized glycerides used as component (A) in the mixtures of theinvention are derived from glycerides having the general formula##STR1## wherein R₁, R₂ and R₃ are each independently hydroxyl or fattyacid groups with the proviso that at least one of R₁, R₂ and R₃ is afatty acid group. The fatty acids may contain from about 12 to about 30carbon atoms in the chain, and the acids may be unsaturated acidscontaining from zero to 3 double bonds.

Preferably the epoxidized glycerides are epoxidized triglycerides whereR₁, R₂ and R₃ are the same or different fatty acid groups. Theepoxidized triglycerides may be and preferably are epoxidized naturaloils such as vegetable, animal and marine oils. Specific examples ofepoxidized oils (triglycerides) which are useful as component (A)include epoxidized vegetable oils such as castor oil, coconut oil, cornoil, cottonseed oil, linseed oil, olive oil, palm oil, peanut oil,rapeseed oil, sesame oil, soybean oil, sunflower oil and tung oil;animal oils such as beef tallow and pig fat; and marine oils such asfish oil. Epoxidized vegetable oils, especially epoxidized soybean oil,are particularly preferred. Epoxidized soybean oil is generally used asa stabilizer for vinyl halide polymers.

The second component (B) of the homogeneous mixtures of the presentinvention may be at least one hydrocarbon-soluble (B-1) basic alkali oralkaline earth metal salt of an alkyl phenol. Throughout thespecification, the term "basic" as applied to the alkali or alkalineearth metal salts useful in the mixtures of the present invention isused to refer to metal salt compositions wherein the ratio of totalmetal contained therein to the organic moieties is greater than astoichiometric ratio of the neutral metal salt. That is, the number ofmetal equivalents is greater than the number of equivalents of theorganic moiety. Such compositions often have been referred to in the artas "overbased" or "superbased" to indicate an excess of the basiccomponent.

The basic alkali or alkaline earth metal salts of alkyl phenols usefulas component (B-1) are known and described in the prior art. Generally,the basic metal salts of alkyl phenols can be prepared by the processcomprising preparing a mixture comprising

(a) at least one alkyl phenol, and

(b) more than one equivalent of at least one alkali or alkaline earthmetal base, per equivalent of said phenol (a), and thereafter treatingsaid mixture with an acidic gas until the titratable basicity has beensubstantially reduced. The titratable basicity of such compositions isdetermined utilizing a phenolphthalein indicator. Generally, themixtures are treated with the acidic gas until the titratable basicityis reduced to a base number of below about 10.

The above process for preparing overbased phenates requires no unusualoperating conditions. The ingredients are mixed, heated and then treatedwith the acidic gas. In some instances, the product mixture obtainedfrom this process may contain a small amount of undissolved materialwhich can be removed conveniently, for example, by filtration.Generally, the reactants are heated prior to treatment with the acidicgas, and the mixture may be heated to a temperature sufficient to driveoff some of the water contained in the mixture. The treatment of themixture with the acidic gas preferably is conducted at elevatedtemperatures, and the range of temperatures required for this step maybe any temperature above ambient temperature up to about 200° C., andmore preferably from a temperature of about 75° C. to about 200° C.Higher temperatures may be used such as 250° C., but there is noapparent advantage in the use of such higher temperatures. Ordinarily, atemperature of about 150° C. is satisfactory.

The alkyl phenol reactant may be derived from phenol itself or fromnaphthol, or from other polynuclear phenolic compounds. It may also be abisphenol such as is obtained from the condensation of an aldehyde witha phenol. The alkyl phenols may contain one or more alkyl groups on thearomatic nucleus, and it is necessary that the number of carbon atoms inthe alkyl groups be sufficient to yield oil-soluble overbased metalphenates. Thus, the alkyl groups on the alkyl phenol will contain atotal of at least 6 carbon atoms, and generally will contain up to about150 carbon atoms. If there is only one alkyl group on the alkyl phenol,the alkyl group will contain at least about 6 carbon atoms, but if thereare two alkyl groups, the sum of the carbon atoms in the two alkylgroups will equal at least about 6. For example, one alkyl group maycontain 2 carbon atoms and the other alkyl group 4 carbon atoms.Specific examples of alkyl groups containing at least 6 carbon atomsinclude hexyl, isoheptyl, diisobutyl, n-decyl, tetrapropyl, octadecyl,polyisobutyl (derived from polyisobutene fractions of various molecularweights) dedecyl, etc. Specific examples of alkyl phenols which arecontemplated for use in the preparation of overbased phenates useful inthe process of the present invention include hexylphenol, heptylphenol,octylphenol, dodecylphenol, octadecylphenol, nonylphenol, and higheralkylated phenols; octylnaphthol, dodecylnaphthol, and higher alkylatednaphthols; a condensation product of formaldehyde and two moles ofoctylphenol, or a condensation product of acetone and two moles ofheptylphenol, etc.

The alkylphenol compound useful in the preparation of the overbasedphenates may contain other groups in addition to the alkyl groups. Thus,halogen, nitro, alkoxy, etc. groups may be present.

The metal bases which are reacted with the alkyl phenols may be alkalior alkaline earth metal bases, although alkaline earth metal bases arepreferred. The basic metal compounds include the metal oxides andhydroxides, and in some instances, the sulfides, hydrosulfides, etc. ofthe alkaline earth metal, calcium and barium are preferred, and the mostpreferred is barium.

By the term "acidic gas" as used in this specification and in the claimsis meant a gas which upon reaction with water will produce an acid.Thus, such gases as sulfur dioxide, sulfur trioxide, carbon dioxide,carbon disulfide, hydrogen sulfide, etc. are exemplary of the acidicgases which are useful in the process of this invention. Of these acids,sulfur dioxide and carbon dioxide are preferred, and the most preferredis carbon dioxide.

As indicated above, the amount of the basic alkali or alkaline earthmetal base utilized in the preparation of the overbased phenates is anamount which is more than one equivalent of the base per equivalent ofthe phenol, and more generally will be an amount sufficient to provideat least three equivalents of the metal base per equivalent of alkylphenol. Larger amounts can be utilized to form more basic compounds, andthe amount of metal base included may be any amount up to that amountwhich is no longer effective to increase the proportion of metal in theproduct.

Procedures for preparing basic alkali and alkaline earth metal salts ofalkyl phenols are well known in the art and is not believed necessary tounduly lengthen the specification with additional description of theprocedures. Examples of patents which describe the preparation of suchbasic metal phenates include, for example, U.S. Pat. Nos. 2,989,463;2,968,642; and 2,971,014, the specifications of which are herebyincorporated by reference for the disclosures of the preparation ofoverbased metal phenates.

The hydrocarbon-soluble basic metal salt useful in the process of thepresent invention may be (B-2) a basic alkali or alkaline earth metalsalt of a monocarboxylic acid. The preparation of such basic salts isknown in the art and any of the basic alkali or alkaline earth metalsalts of monocarboxylic acids are useful in the process and product ofthe present invention. Generally, such basic metal salts are obtained bypreparing a mixture comprising

(a) at least one monocarboxylic acid,

(b) more than one equivalent of at least one alkali metal or alkalineearth metal base per equivalent of said acid, and

(c) optionally and preferably, at least one promoter selected from thegroup of aliphatic alcohols, phenols, or mixtures thereof, andthereafter treating said mixture with an acidic gas until the titratablebasicity of the mixture has been substantially reduced. The alkali metaland alkaline earth metal bases and the acidic gases described above,also are useful in the preparation of the basic monocarboxylic acids ofthis invention. As stated previously, the preferred metal bases are thealkaline earth metal bases, and more preferably the calcium and bariummetal bases. The preferred acidic gases are sulfur dioxide and carbondioxide with carbon dioxide being preferred.

The general procedure of preparing and basic metal salts ofmonocarboxylic acids is similar to the procedure utilized for preparingthe basic phenates described above. The reactants are mixed withstirring and generally with heating to insure thorough mixing, and whereit is desirable to remove water, the temperature of the mixture israised to a temperature sufficient to drive off the water such as at atemperature of above 100° C. The step of treating the mixture with anacidic gas also is as described above and is preferably conducted atelevated temperatures such as above 100° C. A particularly convenientmethod for carrying out the process involves the stirring and heating ofthe mixture to insure an intimate mixture of reactants, heating thismixture to a temperature above 100° C. to remove some water, and thenbubbling an acidic gas through this heated mixture until the titratablebasicity of the mixture has been substantially reduced.

The monocarboxylic acids which can be converted to basic metal saltswhich are useful in the present invention may be aliphatic or aromaticmonocarboxylic acids or mixtures thereof. Among the aliphaticmonocarboxylic acids which can be utilized in the present invention arethe aliphatic monocarboxylic acids containing an average of at leastabout 6 carbon atoms and more generally an average of from about 6 toabout 30 carbon atoms. In most instances the monocarboxylic acid of thealiphatic monocarboxylic acid will be at least one substituted orunsubstituted aliphatic monocarboxylic acid such as n-hexanoic acid,capric acid, caprylic acid, 2-ethylhexanoic acid, undecanoic acid,lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid,linoleic acid, linolenic acid, tung oil acids, tall oil acids,ricinoleic acid, 3,5,5-trimethyl-hexanoic acid, alpha-chlorostearicacid, alphanitrolauric acid, omega-amino-pentadecanoic acid,lauroxy-acetic acid, eicosanoic acid, mono-lauryl adipate, phenyloleicacid, phenylstearic acid, chlorophenylstearic acid, xylylstearic acid,alpha-pyridyloleic acid, tetracosanoic acid, behenic acid, stearolicacid, etc. A preference is expressed for the higher fatty acids such aslauric, palmitic, oleic, linoleic, linolenic, stearic, myristic,palmitic, etc., acids and mixtures of fatty acids containing an averageof at least about 12 carbon atoms.

The monocarboxylic acid also may be an aromatic monocarboxylic acid suchas alkyl aromatic carboxylic acids and hydroxy-substituted aromaticcarboxylic acids. The alkyl aromatic carboxylic acids may contain one ormore alkyl groups such as butyl, hexyl, heptyl, octyl, dodecyl,octadecyl, etc. Generally, the total number of carbon atoms in the alkylgroup(s) is at least 6 and will generally range from about 6 to about150 carbon atoms in the alkyl groups. The aromatic carboxylic acids alsomay contain one or more hydroxyl groups attached to the aromatic moiety.Specific examples of such aromatic carboxylic acids include benzoicacid, salicyclic acid, 4-hexylbenzoic acid, etc.

The preparation of the basic salts of monocarboxylic acids optionallymay be conducted in the presence of (c) at least one promoter selectedfrom the group consisting of aliphatic alcohols, phenols, or mixturesthereof. The alcohols which are useful as promoters include any one ofthe various available substituted or unsubstituted aliphatic orcycloaliphatic alcohols containing from 1 to about 20 or more carbonatoms. In most cases, the alcohol will be unsubstituted, i.e., it willconform to the formula ROH, where R is an aliphatic hydrocarbon radicalor cycloaliphatic hydrocarbon radical containing from 1 to 20 carbonatoms. However, in some instances, the alcohol may contain organicand/or inorganic substituents such as aromatic groups, homocyclicgroups, heterocyclic groups, and nitro, ether, ester, sulfide, keto,amino, nitroso, etc., groups.

Examples of alcohols useful as promoters include methanol, ethanol,n-propanol, isopropanol, n-butanol, isobutanol, n-pentanol-1,n-pentanol-2, isoamyl alcohol, n-hexanol-1, n-hexanol-2,4-methylpentanol-2, n-heptanol, primary isooctanol (prepared forexample, by the well known Oxo process), 2-ethylhexanol, n-octanol,3,5,5-trimethyl-hexanol, cyclohexanol, methyl-cyclohexanol,ethylcyclohexanol, benzyl alcohol, beta-phenethyl alcohol,2-alpha-pyridyl-ethanol-1, tetrahydrofurfuryl alcohol,2-cyclohexyl-ethanol-1, n-decanol, lauryl alcohol, isododecanol(prepared for example, by the hydration of triisobutylene), myristylalcohol, oleyl alcohol, n-eicosanl, n-tricosanol, n-triacontanol,2-phenoxy-ethanol-1, 2-phenoxyethoxyethanol-1, 6-chloro-n-hexanol-1,8-nitro-n-octanol-1, 4-amino-cyclohexanol, ethylene glycol mono-oleate,glyceryl dipalmitate, 2-n-butoxy-ethanol-1, diethylene glycol mono-ethylether, 2-thiobutoxy-ethanol-1, etc. Of the various available alcohols, apreference is expressed for the aliphatic monohydric alcohols.Particularly preferred are the alkanols containing from about 12 toabout 18 carbon atoms. In lieu of a single alcohol, mixtures of two ormore different alcohols may also be used.

The phenols which are optionally present in the herein-described processas promoters include principally substituted and unsubstitutedmonohydric or polyhydric phenols. The substituents may be organic and/orinorganic. Examples of such phenols include phenol itself and alkylatedand cycloalkylated mononuclear or polynuclear phenols containing fromone to 150 or more carbon atoms in the substituent group or groups suchas, for example, ortho-, meta-, and para-cresols; xylenols;para-ethylphenol; ortho, para-diethylphenol; n-propylphenol;para-isopropylphenol; tertiary butylphenol; n-amylphenol; para-tertiaryamylphenol; para-cyclopentylphenol; cyclohexylphenol;methylcyclohexylphenol; secondary-hexylphenol; heptylphenol;diisobutylphenol; 3,5,5-trimethyl-n-hexylphenol; n-decylphenol;cetylphenol; oleylphenol; wax-alkylated phenol; polyisobutenesubstitutedphenol in which the polyisobutene substituent contains from about 20 toabout 150 carbon atoms, etc; aryl-substituted phenols such asphenylphenol, diphenylphenol, and naphthylphenol; polyhydroxy aromaticcompounds such as alizarin, quinizarin, hydroquinone, catechol,pyrogallol, etc.; monohydroxy naphthalenes such as alpha-naphthol andbeta-naphthol; polyhydroxy naphthalenes such as naphthohydroquinone andnaphthoresorcinol; alkylated polyhydroxy aromatic compounds such asoctylcatechol and mono-(triisobutyl) pyrogallol; and substituted phenolssuch as para-nitrophenol, picric acid, ortho-chlorophenol, tertiarybutylchlorophenols, para-nitro ortho-chlorophenol, para-aminophenol, etc. Inmost instances the phenol, if used, will be a mono-alkyl phenolcontaining from about 4 to about 12 carbon atoms in the alkyl group.Thus, commercially available mono-alkyl phenols such as para-tertiarybutylphenol, heptylphenol, and diisobutylphenol (i.e., tertiaryoctylphenol) are preferred.

The amount of the alcohol or phenol which is included in the mixture asa promoter is not critical. The promoters are included in the mixture tocontribute to the utilization of the acidic gas during treatment of themixture with the acidic gas. The amount of alcohol present in themixture prior to treatment with the acidic gas is not critical. However,at least about 0.1 equivalent and preferably from about 0.05 to about 10equivalents of an alcohol or phenol per equivalent of a monocarboxylicgenerally is employed. Larger amounts, for example, up to about 20 toabout 25 equivalents of alcohol or phenol may be used, especially in thecase of lower molecular weight alcohols and phenols. Water, which mayoptionally also be present in the mixture, may be present as water addedas such to the mixture, or the water may be present as "wet alcohol","wet" phenol, hydrates of the alkali or alkaline earth metal salts, orother type of chemically combined water with the metal salts.

In addition to the components described above, the reaction mixturesused to prepare the basic metal salts ordinarily will contain a diluent.Generally, any hydrocarbon diluent can be employed, and the choice ofdiluent is dependent in part on the intended use of the mixture. Mostgenerally, the hydrocarbon diluent will be a non-volatile diluent suchas the various natural and synthetic oils of lubricating viscosity. Thenatural oils include animal oils and vegetable oils (e.g., castor oil,lard oil) as well as solvent-refined or acid-refined mineral lubricatingoils of the paraffinic, naphthenic or mixed paraffinic-naphthenic types.Kerosene can be used. Synthetic oils include hydrocarbon oils andhalo-substituted hydrocarbon oils such as polymerized andinterpolymerized olefins (e.g., polybutylenes, polypropylenes,propylene-isobutylene copolymers, chlorinated polybutylenes, etc.).Other classes of synthetic oils include alkylene oxide polymers andinterpolymers and derivatives thereof; esters of dicarboxylic acids;silicon-based oils; etc.

It is important that an excess of the alkali metal or alkaline earthmetal compound be utilized with respect to the amount of alcohol, alkylphenol and/or monocar- boxylic acid included in the reaction mixture.Thus, if one mole of a carboxylic acid is used, then more than one moleof an alkali metal and more than 0.5 mole of the basic alkaline earthmetal compound must be utilized. Preferably, a stoichiometric excess ofthe alkali or alkaline earth metal compound should be used. As is knownin this art, the basicity of the product which results depends upon theamount of such excess alkali or alkaline earth metal compound includedin the mixture, and the degree to which excess metal is found in theproduct may be described in terms of a "metal ratio". Metal ratio asused herein indicates the ratio of total alkali or alkaline earth metalin the oil-soluble composition to the amount of monocarboxylic acid andphenol and/or alcohol used in the process, on an equivalent basis. Acomposition, for example, having 4 equivalents of barium and 1equivalent of oleic acid as a metal ratio of 4. An oil-solublecomposition having 3.8 equivalents of calcium and 1.9 equivalents ofpalmitic acid has a metal ratio of 2. As much as 15 or more equivalentsof the basic alkali or alkaline earth metal compound, per equivalent ofacid or phenol may be employed with success in this process. Thepreparation of the basic salts of monocarboxylic acids is well known anddifferent procedures have been described in the prior art such as inU.S. Pat. Nos. 3,194,823 and 3,147,232, the disclosures of which arehereby incorporated by reference for their description of suchprocedures.

The following examples illustrate the preparation of the basic metalsalts useful in the invention. Unless otherwise indicated in thefollowing examples and elsewhere in the specification and claims, allparts and percentages are by weight, and temperatures are in degreescentigrade.

EXAMPLE 1

A mixture of 300 grams of mineral oil, 99 grams (0.76 equivalent) ofoctyl alcohol, 257 grams (3.36 equivalents) of barium oxide, 234 grams(0.81 equivalent) of oleic acid, and 45 grams (5 equivalents) of wateris heated with stirring to reflux temperature in about 1 hour. Themixture then is heated to a temperature of 135°-145° C., and maintainedat this temperature for a period of about 0.5 hour. This mixture istreated with CO₂ (2 cubic ft. per hour) at 145° C. for a period of about2 hours. The resulting mixture is heated to 190° C. and filtered. Thefiltrate has the following analysis:

    ______________________________________                                        Sulfate ash          34.5%                                                    Metal ratio          2.9                                                      Neut. No.            0.4 (acidic).                                            ______________________________________                                    

EXAMPLE 2

A mixture of 897 grams of mineral oil, 190 grams (1.15 equivalents) ofoctyl alcohol, 386 grams (4.88 equivalents) of barium oxide, 347 grams(1.22 equivalents) of stearic acid, and 67 grams (7.4 equivalents) ofwater is heated with stirring to reflux temperature in about 1 hour. Themixture then is heated to a temperature of 145° C., and maintained atthis temperature for a period of about 0.5 hour. This mixture is treatedwith CO₂ (2.5 cubic ft. per hour) at 145° C. for a period of about 1.5hours and then heated to 190° C. and filtered. The filtrate has thefollowing analysis:

    ______________________________________                                        Sulfate ash          25.87%                                                   Metal ratio          3.1                                                      Neut. No.            0.3 (acidic).                                            ______________________________________                                    

EXAMPLE 3

A mixture of 2576 grams of mineral oil, 240 grams (1.85 equivalents) ofoctyl alcohol, 740 grams (20.0 equivalents) of calcium hydroxide, 2304grams (8 equivalents) of oleic acid, and 392 grams (12.3 equivalents) ofmethyl alcohol is heated with stirring to a temperature of about 50° C.in about 0.5 hour. This mixture then is treated with CO₂ (3 cubic ft.per hour) at 50°-60° C. for a period of about 3.5 hours. The resultingmixture is heated to 150° C. and filtered. The filtrate has thefollowing analysis:

    ______________________________________                                        Sulfate ash          24.1%                                                    Metal ratio          2.5                                                      Neut. No.            2.0 (acidic).                                            ______________________________________                                    

EXAMPLE 4

A mixture of 932 grams of mineral oil, 100 grams (0.77 equivalent) ofoctyl alcohol, 370 grams (10.0 equivalents) of calcium hydroxide, 287grams (1.0 equivalent) of oleic acid, and 150 grams (4.6 equivalents) ofmethyl alcohol is heated with stirring to a temperature of about 55° C.in about 0.5 hour. This mixture then is treated with CO₂ (2 cubic ft.per hour) at 55° C. for a period of about 6 hours. The resulting mixtureis heated to 150° C. and filtered. The filtrate has the followinganalysis:

    ______________________________________                                        Sulfate ash          30.6%                                                    Metal ratio          7.5                                                      Neut. No.            3.0 (basic).                                             ______________________________________                                    

EXAMPLE 5

A mixture of 1800 grams of mineral oil, 598 grams (4.6 equivalents) ofoctyl alcohol, 952 grams (18.3 equivalents) of strontium oxide, 1376grams (4.88 equivalents) of oleic acid, and 249 grams (27.7 equivalents)of water is heated with stirring to the reflux temperature in about 1.5hours. The mixture is then heated to a temperature of 145° C., andmaintained at this temperature for a period of aobut 0.5 hour. Thismixture is treated with CO₂ (4 cubic ft. per hour) at 145° C. for aperiod of about 1 hour.

EXAMPLE 6

A mixture of 2926 parts of mineral oil, 300 parts (1.56 equivalents) ofheptylphenol and 347 parts (1.64 equivalents) of a mixture of normalC₁₂₋₁₈ primary alcohols in heated to 132° C. under nitrogen, withstirring. Barium hydroxide monohydrate, 248 parts, is added withstirring over one-half hour while water is collected by distillation.When water evolution has ceased, the mixture is dried for 15 minutes at137° C. There is then added 713 parts (2.6 equivalents) of a eutecticmixture of palmitic and stearic acids, followed by 1702 parts (total20.6 equivalents) of barium hydroxide monohydrate, the latter beingadded portionwise over 31/2 hours while water is again removed bydistillation. The temperature is increased to 150° C. during the finalportion of barium hydroxide addition. The mixture is then blown withcarbon dioxide at 150° C. for 21/4 hours and purged with nitrogen at150° C. Finally, a filter aid material is added and the mixture isfiltered, yielding a 53% solution in mineral oil of the desired basicbarium salt which contains 37.06% barium sulfate ash.

EXAMPLE 7

To a mixture of 142 parts (0.5 equivalent) of stearic acid, 134 parts(0.5 equivalent) of oleyl alcohol, 115 parts (0.6 equivalent) ofheptylphenol and 1100 parts of mineral oil is added slowly, at roomtemperature, 674 parts (8 equivalents) of barium oxide. An exothermicreaction takes place which causes the temperature to rise to 70° C.Water, 101 parts, is added gradually, whereupon the temperature rises to120° C. The mixture is held for 4 hours at 130°-140° C. and then heatedto 160° for one-half hour to remove volatile materials. It is then blownwith carbon dioxide at 145°-150° C. until it is neutral tophenolphthalein. Finally, it is filtered using a filter aid material.The filtrate is a 50% solution in mineral oil of the desired basicbarium salt containing 34.99% barium sulfate ash.

EXAMPLE 8

A mixture of 368 parts (1.3 equivalents) of oleic acid, 150 parts (0.8equivalent) of heptylphenol, 260 parts (1.3 equivalents) of tridecylalcohol, 1515 parts of mineral oil and 32 parts of water is heated to76° C., and 184 parts of barium hydroxide monohydrate is added over 7minutes at 76°-92° C. Additional barium hydroxide monohydrate, to atotal of 982 parts (10.4 equivalents), is added over about 2 hours. Themixture is then heated at 145°-157° C. and blown with carbon dioxide for2 hours. After all water has been removed, the product is filtered,yielding a 54% solution in mineral oil of the desired basic barium saltwhich has a barium sulfate ash content of 36.2%.

EXAMPLE 9

Following the procedure of Example 8, a basic barium salt is obtainedfrom 150 parts (0.8 equivalent) of heptylphenol, 368 parts (1.3equivalents) of oleic acid, 982 parts (10.4 equivalents) of bariumhydroxide monohydrate, 370 parts (1.75 equivalents) of a mixture ofnormal C₁₂₋₁₄ primary alcohols, 1405 parts of mineral oil and 32 partsof water. The product contains 36.07% barium sulfate ash.

EXAMPLE 10

Following the procedure of Example 8, a basic barium salt is preparedfrom 150 parts (0.8 equivalent) of heptylphenol, 368 parts (1.3equivalent) of oleic acid, 982 parts (10.4 equivalents) of bariumhydroxide monohydrate, 324 parts (1.3 equivalents) of oleyl alcohol,1451 parts of mineral oil and 32 parts of water. The product, a 56%solution in mineral oil, contains 35.65% barium sulfate ash.

EXAMPLE 11

Following the procedure of Example 8, a basic barium salt is preparedfrom 720 parts (2.6 equivalents) of tall oil acid, 300 parts (1.56equivalents) of heptylphenol, 1900 parts (20.1 equivalents) of bariumhydroxide monohydrate, 374 parts (1.64 equivalents) of a mixture ofnormal C₁₂₋₁₈ primary alcohols and 65 parts of water. The product, a 53%solution in mineral oil of the desired basic salt, contains 37.79%barium sulfate ash.

EXAMPLE 12

A mixture of 300 parts (1.56 equivalents) of heptylphenol, 347 parts(1.64 equivalents) of a mixture of normal C₁₂₋₁₈ primary alcohols and2000 parts of mineral oil is heated to 100°-105° C., and 1960 parts(20.7 equivalents) of barium hydroxide monohydrate is added over 18minutes. The mixture is heated to 150° C. and water is collected bydistillation. After 98 parts of water have been collected, 360 parts oftall oil acid is added over 20 minutes. Water distillation is continuedfor 21/2 hours, and then an additional 360 parts (total 2.6 equivalents)of tall oil acid is added. After an additional one-half hour of heating,the mixture is blown with carbon dioxide at 145°-150° C. for 3 hours.The mixture is purged with nitrogen until substantially all volatilematter has been removed and then 1098 parts of mineral oil is added andthe mixture is filtered, using a filter aid material. The filtrate isthe desired 51% solution of a basic barium salt containing 36.6% bariumsulfate ash.

EXAMPLE 13

A mixture of 225 parts of mineral oil and 100 parts of dodecylphenol isprepared, purged with nitrogen and heated to about 90° C. whereupon214.6 parts of barium hydroxide monohydrate are added over a period ofabout 1 hour. The mixture then is heated to about 150° C. and treatedwith carbon dioxide while maintaining the temperature at about 150°-155°C. for about 2 hours while removing water. After all of the water hasbeen removed, the material is filtered yielding the desired productwhich is adjusted with additional mineral oil to form an oil solutioncontaining 28.5% barium and about 43% mineral oil.

EXAMPLE 14

A mixture of 65 parts of commercially available mixture of aliphaticalcohols containing 12 to 18 carbon atoms, 141 parts of nonylphenol and600 parts of mineral oil is prepared and purged with nitrogen to removeany oxygen present in the system. The nitrogen purge is maintainedthroughout the entire process. After a period of about 20 minutes, themixture is heated while stirring to a temperature of from about 90° C.to about 98° C. At this temperature, 1200 parts of barium hydroxidemonohydrate is added incrementally over a 30-minute period and thetemperature of the mixture is then increased to about 150°-155° C. whileremoving any water which is driven off during the heating. Oleic acid(258 parts) is then added over a 30-40 minute period while againremoving the water of reaction which comes over. After all of the oleicacid is added, the mixture is treated with carbon dioxide at a rate ofabout 2 SCFH for approximately 4 hours while monitoring the titratablebasicity of the mixture. The base number of the final product is about8.

EXAMPLE 15

The general procedure of Example 14 is repeated utilizing 325 parts ofthe alcohol mixture containing from 12 to 18 carbon atoms, 675 parts ofa tall oil fatty acid, 1870 parts of mineral oil, 1840 parts of bariumhydroxide monohydrate, and 281 parts of nonylphenol. At the end of thereaction, the filtrate is adjusted with mineral oil to provide a productcontaining 20.6% barium and a sulfate ash of 35.0%.

In some instances, it is desirable to post-treat the basic metal saltsof alkyl phenols (B-1) and the basic metal salts of monocarboxylic acids(B-2) prepared utilizing phenols are promoters with at least onecompound capable of displacing the hydrogen of any phenolic hydroxylgroups remaining in the product mixture. It has been observed that whenthe phenol-containing products are treated in this manner, improvedcolor and color stability is obtained. A variety of compounds arecapable of displacing the hydrogen of the phenolic hydroxyl group, andthese include epoxy compounds, phosgene, diazomethane, metal alkoxides,metal sulfoxides, carbonates, isocyanates, etc. The amount of suchcompounds which is reacted with the phenol-containing basic productspreferably is an amount which is sufficient to react and displace all ofthe hydrogens on the phenolic hydroxyl groups present.

Preferably, the above-described basic compositions are post-treated withat least one epoxide. Although any epoxy compound which is capable ofreacting with the hydrogen atom of the phenolic hydroxyl group can beutilized beneficially, it generally is preferred that the epoxide be alow molecular weight epoxide such as ethylene oxide, propylene oxide,butylene oxide, epichlorohydrin, butyl epoxy stearate, glycidylmethacrylate, etc. Particularly preferred are the lower alkyl epoxidescontaining 7 carbons or less, and especially ethylene and propyleneoxides.

The reaction between the compound capable of displacing hydrogen in thephenolic hydroxyl group such as the epoxides, and the basic compositionscontaining phenol is generally carried out at about from ambienttemperature to about 200° C. The most convenient method is to introducethe epoxide gradually into the basic composition which is usuallydissolved in a suitable non-polar solvent such as mineral oil, kerosene,or the like.

The following example illustrate the post-treatment of the basiccompositions containing or derived from phenol with a reactive compoundsuch as an epoxide.

EXAMPLE 16

The basic barium salt obtained in Example 14 is maintained in a nitrogenatmosphere and propylene oxide is fed into the composition (about 73parts) over a period of about 30-40 minutes while maintaining thetemperature of the reaction mixture at about 150° C. The mixture is thenfiltered while hot, and the filtrate is the desired productcharacterized by a base number of 10 and a barium content of 35%.

In addition to the epoxidized glycerides (A) and the hydrocarbon-solublebasic metal salts (B), the mixtures which are treated in accordance withthe process of the present invention also contain (C) a hydrocarbondiluent. Such mixtures, even though including a hydrocarbon diluent arenon-homogeneous mixtures but can be rendered homogeneous by heating atan elevated temperature until the mixture becomes homogeneous.

Generally, any hydrocarbon diluent can be employed, and the choice ofdiluent is dependent in part on the intended use of the mixture. Mostgenerally, the hydrocarbon diluent will be a non-volatile diluent suchas the various natural and synthetic oils of lubricating viscosity. Thenatural oils include animal oils and vegetable oils (e.g., castor oil,lard oil) as well as solvent-refined or acid-refined mineral lubricatingoils of the paraffinic, naphthenic or mixed paraffinic-naphthenic types.Synthetic oils include hydrocarbon oils and halo-substituted hydrocarbonoils such as polymerized and interpolymerized olefins (e.g.,polybutylenes, polypropylenes, propylene-isobutylene copolymers,chlorinated polybutylenes, etc.). Other classes of synthetic oilsinclude alkylene oxide polymers and interpolymers and derivativesthereof; esters of dicarboxylic acids; silicon-based oils; etc. In mostinstances, the basic metal salts (B-1) and (B-2) are prepared frommixtures containing non-volatile hydrocarbon diluents such as mineraloil, and thus, the hydrocarbon diluent (C) in some instances, may bederived exclusively from the diluent present in said basic metal salts.In other words, the non-homogeneous mixture which is treated inaccordance with the present invention is prepared by mixing (A) at leastone epoxidized triglyceride with at least one oil solution of ahydrocarbon-soluble basic metal salt (B-1) and/or (B-2). Additionalsolvent can be added as desired. When the basic metal salt (B-1) and/or(B-2) and (C) comprise a hydrocarbon solution of the salt, suchsolutions may contain the metal in various concentrations. For example,hydrocarbon solutions of the metal salts (B-1) and/or (B-2) can beprepared containing from about 15 to about 45% barium. Other solutionscan be prepared containing from about 5 to about 20% of calcium.

As mentioned previously the process of the present invention comprisesheating a non-homogeneous mixture of the type described above to anelevated temperature until the mixture is homogeneous. Temperaturesabove about ambient temperature and more generally above 40° C. to ashigh as 150° C. or higher, although higher temperatures do not appear tobe necessary or desirable. Generally, the mixture of components (A), (B)and (C) is heated to a temperature of about 80° C. for a period of about0.5 hour. The temperature and time of heating can be readily determinedby one skilled in the art and for each individual mixture. Once themixture has been rendered homogeneous by heating, the mixture may becooled to ambient temperature and retains the homogeneous nature.Moreover, the homogeneity of the mixture is maintained for extendedperiods of time.

The relative amounts of components (A), (B) and (C) incorporated intothe mixture can be varied over a wide range and will be dependent uponthe desired end use for the mixture once it has been renderedhomogeneous. Generally, the weight ratio of component (A) to component(B) will vary from about 1:10 to about 10:1. The amount of hydrocarbondiluent (component (C)) present in the mixture will be a minor amount(e.g., up to about 20% by weight), and is an amount which results in anon-homogeneous mixture.

The following examples (except those identified as Control examples)illustrate the process of the present invention for preparinghomogeneous mixtures.

CONTROL-1

A mixture of 12.3 parts of the product of Example 16 and 8 parts ofepoxidized soybean oil (Drapex 6.8) is prepared at room temperature withstirring. The mixture remains non-homogeneous despite extended stirring,and does not become homogeneous when stirring is terminated and themixture is allowed to stand at ambient temperature for an extendedperiod of time.

CONTROL-2

A mixture of 47.6 parts of the oil solution prepared in Example 16 and32 parts of epoxidized soybean oil is prepared at ambient temperature.This mixture remains non-homogeneous at ambient temperature even whenstirred for an extended period of time.

EXAMPLE A

A sample of a non-homogeneous mixture obtained in Control-2 in a 4-ouncebottle is placed in an oven at a temperature of about 162° C. for about30 minutes. The mixture becomes homogeneous.

EXAMPLES B-J

The procedure of Example A is repeated with the following mixtures whichare initially non-homogeneous but become homogeneous on heating.

                  TABLE I                                                         ______________________________________                                        Ex-                                                                           am-  Basic Barium Salt                                                                             Epoxidized Oil % Ba in                                   ple  Source    Amount(g) Type   Amount(g)                                                                             Product                               ______________________________________                                        B    Example 13                                                                              30        Soybean                                                                              20      17.07                                 C    Example 13                                                                              40        Soybean                                                                              10      22.76                                 D    Example 13                                                                              45        Soybean                                                                              5       25.60                                 E    Example 13                                                                              47.5      Soybean                                                                              2.5     27.03                                 F    Example 16                                                                              30        Soybean                                                                              20      20.64                                 G    Example 16                                                                              40        Soybean                                                                              10      27.52                                 H    Example 16                                                                              45        Soybean                                                                              5       30.96                                 I    Example 16                                                                              47.5      Soybean                                                                              2.5     32.68                                 J    Example 13                                                                              14.4      Soybean                                                                              40      7.53                                  ______________________________________                                    

The liquid homogeneous stabilizer compositions prepared in accordancewith the process of the present invention may contain in addition to theepoxidized glyceride (A) and the hydrocarbon-soluble basic alkali oralkaline earth metal salts (B-1) or (B-2) and (C) hydrocarbon diluent,(D) at least one neutral polyvalent metal salt of a carboxylic acid. Inaccordance with the procedure of the present invention, after thenon-homogeneous stabilizer compositions have been rendered homogeneousin accordance with the present invention, one or more polyvalent metalsalts of carboxylic acids can be blended into the homogeneouscomposition and the composition retains its homogeneity. The polyvalentmetal salts which may optionally be used in addition to theabove-described basic alkali or alkaline earth metal salts (B-1) and(B-2) are most often neutral metal salts of cadmium, zinc, zirconium,tin, calcium, strontium, or mixtures thereof, the preferred salts beingcadmium salts and mixtures of cadmium and zinc salts.

The optional polyvalent metal salts generally will be salts of aliphaticor benzenoid monocarboxylic acids. The useful aliphatic acids arestraight-chain and branched-chain alkanoic acids having from 2 to about22 carbon atoms and preferably from about 6 to about 12 carbon atoms.Examples of the preferred aliphatic acids are caproic acid,2-ethylhexanoic acid, caprylic, neooctanoic acid, neodecanoic acid,pelargonic acid, lauric acid, malmitic acid, myristic acid, stearicacid, behenic acid, oleic acid, linoleic acid, etc. Examples of aromaticcarboxylic acids that can be utilized in the formation of the polyvalentmetal salts include benzoic acid, ortho-, meta-, and para-toluic acid,ortho-, meta-, and para-ethylbenzoic acid, ortho-, meta-, and para-,butylbenzoic acid, chlorobenzoic acid, bromobenzoic acid and hydroxybenzoic acid. When included in the stabilizer systems of this invention,the neutral polyvalent metal salts generally will be present in amountsfrom about 1 to about 20% by weight.

The homogeneous stabilizer compositions of the present invention alsomay include (E) one or more organic phosphite. The organic phosphiteuseful in the stabilizer compositions of the present invention can beany organic phosphite having one or more organic groups attached tophosphorus through oxygen. More generally, the organic phosphitecomponent of the stabilizer systems of the present invention generallywill be secondary or tertiary phosphites having 2 or 3 organic groupsattached to the phosphorus through oxygen, and most often, these groupsare monovalent groups. Thus, the phosphites may be secondary phosphitessuch as diaryl phosphites, aryl alkyl phosphites and dialkyl phosphites,or tertiary phosphites, such as trialkyl phosphites, triaryl phosphites,dialkyl monoaryl phosphites and monoalkyl diaryl phosphites. Also usefulare cyclic phosphites derived from pentaerithitol and other neopentylpolyhydric alcohols. A preferred group of phosphites are the trialkyl,triaryl, dialkyl monoaryl, and monoalkyl diaryl phosphites in which thealkyl groups are straight-chain or branched-chain groups having fromabout 3 to about 18 carbon atoms and preferably from about 4 to about 10carbon atoms, and the aryl groups are phenyl groups or substitutedphenyl groups in which the substituents are halogen, hydroxyl groups oralkyl groups having from 1 to about 12 carbon atoms. Specific examplesof useful organic phosphites include: triphenyl phosphite, tri-(p-tertbutylphenyl) phosphite, tri-(hydroxyphenyl) phosphite, diphenylphosphite, diphenyl dodecyl phosphite, phenyl di-2-ethylhexyl phosphite,phenyl didecyl phosphite, di-(nonylphenyl) 2-chloroethyl phosphite,tridodecyl phosphite, trioctadecyl phosphite, and the like. Anotherpreferred group of phosphites are the secondary phosphites that containthe aforementioned aryl and/or alkyl groups. These include, for example,diphenyl hydrogen phosphite, di(chlorophenyl) hydrogen phosphite,octaphenyl octyl hydrogen phosphite, phenyl decyl hydrogen phosphite,phenyl octadecyl hydrogen phosphite, di-2-ethylhexyl phosphite, andhexyl decyl phosphite. A single phosphite or a mixture of two or more ofthese compounds may be used.

When the non-homogeneous stabilizer compositions have been renderedhomogeneous in accordance with the process of the present invention, itis also sometimes desirable to add volatile solvents to the stabilizercompositions of the present invention as a diluent prior to use as astabilizer in vinyl halide polymers. Examples of solvents which can beutilized include the aliphatic, cycloaliphatic and aromatichydrocarbons, the aliphatic, cycloaliphatic and aromatic alcohols, etheralcohols, and ether alcohol esters. Kerosene is an often used diluent inpolymer stabilizer systems.

It also is desirable in some instances to add additional epoxidizedsoybean oil to the homogeneous compositions once they have been renderedhomogeneous in accordance with the present invention. It has beenobserved in some instances that attempts to convert non-homogeneousliquids to homogeneous liquids containing large amounts of epoxidizedtriglycerides are not successful whereas a preliminary conversion of amixture containing lesser amounts of epoxidized triglyceride and thebasic metal salts to a homogeneous solution followed by the addition ofthe remaining epoxidized triglyceride results in a mixture containingthe desirable amount of epoxidized triglyceride, and the mixture retainsits homogeneity.

In addition to the afore-mentioned components, the stabilizercompositions of the present invention may contain other heat and lightstabilizers such as organo tin compounds antioxidants, lubricants,peptizing agents and other additives that are ordinarily employed in theproduction of stabilizers for vinyl halide polymers.

The following examples illustrate the stabilizer compositions of thepresent invention containing components in addition to the epoxidizedtriglyceride and the basic alkali or alkaline earth metal salt. Thefollowing Examples K-M of homogeneous stabilizing compositions areobtained by first preparing a homogeneous clear solution of theindicated epoxidized triglyceride and basic alkali or alkaline earthmetal salt in accordance with the method of the invention and thereafterblending the other components into the homogeneous mixture. In ExamplesK, L and M, described in Table II, the components are added in the ordergiven in Table II at room temperature.

                  TABLE II                                                        ______________________________________                                                       Example                                                        Components       K.sup.1   L      M                                           ______________________________________                                        Product of Example A                                                                           19.9      19.9   19.9                                        Cadmium Octoate.sup.2                                                                          8.4       8.4    8.4                                         Triphenyl phosphite (TPP)                                                                      8.0       8.0    8.0                                         Kerosene         3.7       3.7    3.7                                         Epoxidized Soybean Oil                                                                         --        8.0    40.0                                        Condition of Blend                                                            initial          clear     clear  clear                                       after 2.5        clear     clear  clear                                       months                                                                        ______________________________________                                         .sup.1 Numbers are weight in grams.                                           .sup.2 Available from Synthetic Products, Inc. under general trade            designation "SYNPRON 1202".                                              

Stabilizer compositions containing additional components such asphosphites and neutral metal salts can also be prepared from thehomogeneous products of Examples B-I. The preparation of such stabilizercompositions is illustrated in Table III. In Examples N-U, thecomponents are added in the order given in Table III at room temperaturewith stirring.

                  TABLE III                                                       ______________________________________                                        Components                                                                    Product of                                                                             Examples                                                             Example  N      O      P    Q    R    S    T    U                             ______________________________________                                        B        23.98                                                                C               17.99                                                         D                      15.99                                                  E                           15.14                                             F                                19.83                                        G                                     14.88                                   H                                          13.22                              I                                               12.53                         Kerosene --     5.61   7.61 8.46 3.77 8.72 10.38                                                                              11.07                         Cadmium  8.4    8.4    8.4  8.4  8.4  8.4  8.4  8.4                           octoate                                                                       Triphenyl                                                                              8.0    8.0    8.0  8.0  8.0  8.0  8.0  8.0                           phosphite                                                                     (TPP)                                                                         Results                                                                       Initial cond.                                                                          clear  →                                                                             →                                                                           →                                                                           →                                                                           →                                                                           →                                                                           clear                         overnight                                                                              clear  →                                                                             →                                                                           →                                                                           →                                                                           →                                                                           cldy.                                                                              cldy.                         one week clear  →                                                                             →                                                                           →                                                                           →                                                                           →                                                                           cldy.                                                                              cldy.                         two months                                                                             clear  →                                                                             →                                                                           →                                                                           sl.  sl.  cldy.                                                                              cldy.                                                          cldy.                                                                              cldy.                                   ______________________________________                                    

EXAMPLE V

A homogeneous stabilizer composition is prepared from the composition ofExample J by adding to the stirred product of Example J, 9.21 grams ofkerosene, 8.4 grams of cadmium octoate and 8.0 grams of triphenylphosphite in that order. This composition contains a large amount of theepoxidized soybean oil which is desired in vinyl halide stabilization,and the composition is homogeneous.

The homogeneous stabilizer compositions of the invention are readilyadaptable for use as stabilizers in plastic formulations such as vinylhalide polymers and copolymers as well as other polymers such aspolyethylene, polyisobutylene, polystyrene, copolymers of isobutylenewith isoprene, butadiene, styrene and the like.

Vinyl halide polymers and other halogen containing resins that can bestabilized with the basic alkali and alkaline earth metal saltcomposition of this invention include polyvinylchloride,polyvinylbromide, polyvinylfluoride, polyvinylidenechloride, chlorinatedpolyethylene, chlorinated polypropylene, brominated polyethylene, rubberhydrochloride, vinylchloride-vinyl-acetate copolymer,vinylchloride-ethylene copolymer, vinylchloride propylene copolymer,vinylchloridestyrene copolymer, vinylchloride-isobutylene copolymer,vinylchloride-vinylidenechloride copolymer,vinylchloride-styrene-acrylonitrile-terpolymer, vinylchloride-butadienecopolymer, vinylchloride-isoprene copolymer, vinylchloride-chlorinatedpropylene copolymer, vinylchloride-vinylidenechloride-vinylacetateterpolymer, vinylchloride-ethyl-acrylate copolymer,vinylchloride-maleate-copolymer, vinylchloride-methylmethacrylatecopolymer, vinylchloride-acrylonitrile copolymer, internally plasticizedpolyvinylchloride, and blends of the above halogen-containing resin andalpha-olefin polymers. The terms "polyvinylchloride" and "vinyl chloridepolymer" as used herein include any polymer formed at least in part ofthe recurring group, ##STR2## and having a chlorine content of excess of40%. In this group, the X groups can each be either hydrogen orchlorine. In polyvinyl chloride homopolymers, each of the X groups ishydrogen. Thus, the term includes not only polyvinyl chloridehomopolymers but also after-chlorinated polyvinyl chlorides as a class,for example, those disclosed in British Pat. No. 893,288 and alsocopolymers of vinyl chloride in a major proportion and othercopolymerizable monomers in a minor proportion, as already mentioned.

The invention also is applicable to mixtures of polyvinyl chloride in amajor proportion with a minor proportion of other synthetic resins suchas chlorinated polyethylene or copolymers of acrylonitrile withbutadiene and styrene.

In addition to the homogeneous stabilizer compositions of this inventiondescribed above, the stabilized vinyl halide polymer compositions maycontain other additives such as pigments, dies, processing aids, impactmodifiers, extenders, and lubricants, the amount is ordinarily employedfor the purposes indicated.

The vinyl halide polymers stabilized with the compositions of thepresent invention may be prepared by any suitable and convenientprocedure. Such procedures include dry blending with a conventional mixsuch as a Henschel blender, mixing on a two or three roll heat mill, andtumbling.

The amount of the stabilizer compositions of the present inventionutilized in stabilizing polymer compositions, especially vinyl halidepolymer compositions, is an amount which is sufficient to provide thedesired stabilizing properties. The amount of the homogeneouscompositions of the present invention added to vinyl halide polymersalso will be dependent upon the relative amounts of the variouscomponents contained in the homogeneous composition, and such amountscan be readily determined by one skilled in the art of vinyl halideformulations. In general, vinyl halide polymers may be formulated tocontain from about 0.1 to about 10 parts by weight per 100 parts ofvinyl halide polymer, of the stabilizer compositions of the presentinvention, and the stabilizer compositions generally will comprise fromabout 1% to about 20% by weight of the neutral polyvalent metal and 1%to about 20% by weight of phosphorus per part by weight of the basicmetal salt.

The utility of the homogeneous stabilizer compositions of the presentinvention is demonstrated by the following examples wherein thecompositions of the invention are utilized as stabilizers in the vinylhalide formulation comprising 200 grams of GEON 30, 100 grams ofdioctylphthalate and 0.5 gram of stearic acid. The stabilizers inExamples II-V are premixed and thereafter blended with the GEON 30mixture until uniform. The formulation is process on a two roll mill for10 minutes; the front roll is maintained at about 160° C. and the backroll at about 150° C. The vinyl halide formulations prepared in thismanner are identified in the following Table IV. The initial color ofthe vinyl halide polymers formed in this manner is observed and recordedin Table IV. The heat stability of the vinyl halide polymers obtained inExamples I-V is observed and is summarized also in Table IV.

                  TABLE IV                                                        ______________________________________                                        Comparison of Vinyl Halide Systems                                            ______________________________________                                               Stabilizer                                                             Example  Source       Amount(g) Initial Color                                 ______________________________________                                        I        Prod. of Ex. J                                                                             810       clear                                         II       Prod. of Ex. 13                                                                            1.44                                                             Cd Octoate   0.84                                                             T.P.P.       0.80                                                             Epox. Soybean                                                                              4.00      clear                                         III      Prod. of Ex. R                                                                             4.00                                                             Epox. Soybean                                                                              4.00      clear                                         IV       Prod. of Ex. 16                                                                            1.20                                                             Cd Octoate   0.84                                                             T.P.P.       0.80                                                             Epox. Soybean                                                                              4.00      clear                                         V        Barium Octoate                                                                             2.56                                                             Cd Octoate   0.84                                                             T.P.P.       0.80                                                             Epox. Soybean                                                                              4.00      clear                                         ______________________________________                                                Heat Stability (180° C.)*                                      Example   15 min. 30 min.    60 min.                                                                             120 min.                                   ______________________________________                                        I         clear   v.sl.yel.  sl.yel.                                                                             yel.                                       II        clear   v.sl.yel.  sl.yel.                                                                             yel.                                       III       clear   v.sl.yel.  sl.yel.                                                                             yel.                                       IV        clear   v.sl.yel.  sl.yel.                                                                             yel.                                       V         clear   clear      sl.yel.                                                                             yel.                                       ______________________________________                                         *Heat stability is run on 0.060" milled sheets of polymer in oven test.  

I claim:
 1. A process for preparing liquid homogeneous stabilizer compositions for vinyl halide polymers which comprises heating a non-homogeneous mixture comprising(A) at least one epoxidized glyceride wherein the glyceride is represented by the formula ##STR3## wherein R₁, R₂ and R₃ are each independently hydroxy or fatty acid groups of from about 12 to about 30 carbon atoms with the proviso that at least one of R₁, R₂ and R₃ is a fatty acid group, (B) at least one hydrocarbon-soluble(B-2) basic alkali or alkaline earth metal salt of a monocarboxylic acid, and (C) a hydrocarbon diluent, at an elevated temperature until the mixture is homogeneous.
 2. The process of claim 1 wherein the basic salt (B-2) is prepared utilizing a phenol as a promoter.
 3. The process of claim 2 wherein the basic salt (B-2) has been post-treated with at least one compound capable of displacing the hydrogen of the phenolic hydroxyl group.
 4. The process of claim 3 wherein the compound capable of displacing the hydrogen is an epoxide.
 5. The process of claim 4 wherein the epoxide is ethylene oxide or propylene oxide.
 6. The process of claim 1 wherein the metal (B-2) are alkaline earth metal salts.
 7. The process of claim 1 wherein the metal (B-2) are barium or calcium salts.
 8. The process of claim 1 wherein the glyceride is a triglyceride.
 9. The process of claim 1 wherein the epoxidized glyceride is an epoxidized vegetable oil.
 10. The process of claim 1 wherein the basic metal salt (B-2) is obtained by preparing a mixture comprising(a) at least one aliphatic or aromatic monocarboxylic acid, (b) more than one equivalent of at least one alkali metal or alkaline earth metal base per equivalent of said acid, and (c) at least one promoter selected from the group of aliphatic alcohols, alkyl phenols, or mixtures thereof and thereafter treating said mixture with an acidic gas until the titratable basicity (phenolphthalein indicator) of the mixture has been substantially reduced.
 11. The process of claim 10 wherein the monocarboxylic acid (a) is selected from the group consisting of aliphatic monocarboxylic acids containing an average of from about 6 to about 30 carbon atoms and alkyl aromatic acids having one or more alkyl groups wherein the total number of carbon atoms in the alkyl group or groups is at least about
 6. 12. The process of claim 11 wherein (a) is an aliphatic monocarboxylic acid.
 13. The process of claim 12 wherein the monocarboxylic acid is a fatty acid.
 14. The process of claim 10 wherein (c) is a mixture of an aliphatic alcohol and an alkyl phenol.
 15. The process of claim 10 wherein the aliphatic alcohol (c) contains from one to about 30 carbon atoms.
 16. The process of claim 14 wherein the alkyl phenol contains one or more alkyl groups containing a total of from about 6 to about 150 carbon atoms.
 17. The process of claim 10 wherein the base (b) is an alkaline earth metal base.
 18. The process of claim 17 wherein the alkaline earth metal base is a barium base.
 19. The process of according to claim 10 wherein the ratio of equivalents of the alkaline earth metal base (b) to the combination of components (a) and (c) is at least about 3:1.
 20. The process of claim 10 wherein the acidic gas is sulfur dioxide or carbon dioxide.
 21. The process of claim 10 wherein the acidic gas is carbon dioxide.
 22. A process for preparing a liquid homogeneous stabilizer composition for vinyl halide polymers which comprises heating a non-homogeneous mixture comprising(A) at least one epoxidized vegetable oil, (B-2) at least one hydrocarbon-soluble basic alkaline earth metal salt of an aliphatic or aromatic monocarboxylic acid, and (C) a non-volatile hydrocarbon diluent, at an elevated temperature until the mixture is homogeneous.
 23. The process of claim 22 wherein the basic salt (B-2) is prepared utilizing as a promoter an alkyl phenol, an aliphatic alcohol, or mixtures thereof.
 24. The process of claim 22 wherein the basic alkaline earth metal salt (B-2) is obtained by preparing the mixture comprising(a) at least one aliphatic or aromatic monocarboxylic acid, (b) more than one equivalent of at least one alkaline earth metal base per equivalent of said acid, and (c) at least one aliphatic alcohol, alkyl phenol, or mixtures thereof, heating the mixture to an elevated temperature, and thereafter treating said mixture with carbon dioxide until the titratable basicity (phenolphthalein indicator) of the mixture has been substantially reduced.
 25. The process of claim 24 wherein the basic salt (B-2) is post-treated with at least one compound capable of displacing the hydrogen from the phenolic OH group.
 26. The process of claim 22 wherein the alkaline earth metal salt is a barium or calcium salt.
 27. The process of claim 24 wherein the metal base (b) is a barium base, and the mixture is heated to a temperature in excess of 100° C. to remove at least some of the water present in the mixture.
 28. The process of claim 24 wherein (a) is an aliphatic monocarboxylic acid containing an average of from about 6 to about 30 carbon atoms.
 29. The process of claim 28 wherein the monocarboxylic acid is a fatty acid.
 30. The process of claim 24 wherein the phenol contains one or more alkyl groups containing a total of from about 6 to about 150 carbon atoms.
 31. The process of claim 24 wherein the ratio of equivalents of the alkaline earth metal base (b) to the combination of components (a) and (c) is at least about 3:1.
 32. The process of claim 22 wherein the mixture of components (A), (B-2) and (C) is heated to a temperature of from about 40° C. to about 150° C.
 33. A stabilizer composition prepared in accordance with the process of claim
 1. 34. A stabilizer composition prepared in accordance with the process of claim
 22. 35. A stabilizer composition prepared in accordance with the process of claim
 24. 36. A homogeneous stabilizer composition for vinyl halide polymers which comprises a mixture of the composition of claim 23, (D) at least one neutral polyvalent metal salt of a carboxylic acid and/or (E) at least one organic phosphite.
 37. A homogeneous stabilizer composition for vinyl halide polymers which comprises a mixture of the composition of claim 34, (D) at least one neutral polyvalent metal salt of a carboxylic acid and/or (E) at least one organic phosphite.
 38. A homogeneous stabilizer composition for vinyl halide polymers which comprises a mixture of the composition of claim 35, (D) at least one neutral polyvalent metal salt of a carboxylic acid and/or (E) at least one organic phosphite.
 39. The composition of claim 36 wherein the polyvalent metal salt (E) is a substantially neutral cadmium, zinc, zirconium, tin or calcium salt of an aliphatic or aromatic carboxylic acid or mixtures thereof.
 40. The composition of claim 36 wherein the mixture comprises from about 1% to about 20% by weight of the polyvalent metal, and 1% to about 20% by weight of phosphorus per part by weight of the basic metal salt.
 41. The composition of claim 40 wherein the mixture also contains up to about 20% by weight of additional hydrocarbon solvent.
 42. The composition of claim 36 wherein the polyvalent metal salt (E) is a cadmium salt of an aliphatic monocarboxylic acid containing from 2 to 22 carbon atoms.
 43. The composition of claim 36 wherein the organic phosphite is a secondary or tertiary alkyl, aryl or alkyl aryl phosphite.
 44. The composition of claim 36 wherein the phosphite is selected from the group consisting of secondary and tertiary aryl, alkyl, and alkyl aryl phosphites in which the alkyl groups have from about 3 to about 18 carbon atoms and the aryl groups are phenyl, alkyl phenyl, halo phenyl or hydroxy phenyl groups.
 45. The vinyl halide polymer composition comprising a vinyl halide polymer and a stabilizing amount of the homogeneous stabilizer composition of claim
 33. 46. The vinyl halide polymer composition comprising a vinyl halide polymer and a stabilizing amount of the homogeneous stabilizer composition of claim
 34. 47. The vinyl halide polymer composition comprising a vinyl halide polymer and a stabilizing amount of the homogeneous stabilizer composition of claim
 35. 48. The vinyl halide polymer of claim 45 containing from about 0.1 to about 10 parts by weight per 100 parts of said vinyl halide polymer of the stabilizer composition.
 49. The vinyl halide polymer of claim 46 containing from about 0.1 to about 10 parts by weight per 100 parts of said vinyl halide polymer of the stabilizer composition. 